AB1325 DIAGNOSTIC DELAY IN FAMILIAL MEDITERRANEAN FEVER: IS IT STILL A PROBLEM?
Authors: M. B. Yuzbasioglu, A. Y. Ayla, I. Besiroglu, S. N. Baspinar, S. Yenigun, I. Durucan, A. Alkan, M. E. Gazioglu, M. F. Hiyamli, I. Sarac, H. Ozdogan, S. Ugurlu
Journal: Annals of the Rheumatic Diseases (2022)

Background Familial Mediterranean fever (FMF) is a rare hereditary autoinflammatory disease with disease onset in childhood in most cases. Although autoinflammatory disease awareness is increasing among physicians, delayed diagnosis is still prevalent as a cause of greater morbidity[1]. Objectives We aimed to study the characteristics of FMF patients diagnosed between 2000-2010 and 2011-2021 and to see if there was a difference in diagnostic delay. Methods We retrospectively evaluated the medical records of the FMF patients followed up in our rheumatology clinic that were diagnosed between 2000-2021 and split them into two groups according to the year they received their diagnosis. There were 1151 patients diagnosed between 2000-2010 (Group 1) and 821 patients diagnosed between 2011-2021 (Group 2). The data studied included gender, age of onset, diagnostic delay, attack characteristics, MEFV mutation, and family history. Results The median current age of patients in Group 1 is 37 years (IQR:30-46) and the median current age of the patients in Group 2 is 36 years (IQR:29-44). The female to male ratio was 1.57 in Group 1 and 1.75 in Group 2, with no significant difference between the groups. Group 2 had later disease onset (p&lt;0.001) and later diagnosis (p&lt;0.001) than Group 1 as shown in the Table 1. The proportion of patients with at least one M694V mutation was higher in Group 2 (p&lt;0.001). The attack durations did not vary between the groups. There was no significant difference in the prevalence of abdominal pain, fever, arthritis, and arthralgia between Group 1 and Group 2. Chest pain (p=0.005), myalgia (p&lt;0.001), and erysipelas-like erythema (p=0.041) were more common in Group 2 than Group 1. Patients with positive family history were more frequent in Group 2 than Group 1 (p=0.046). Table 1. Group 1 (2000-2010, n=1151) Group 2 (2011-2021, n=821) p Female/Male, n 704/447 522/299 0.275 Age at onset, median (IQR) years 13 (7-21) 18 (12-26) &lt;0.001 Delay in diagnosis, median (IQR) years 4 (1-11) 5,5(2-15) &lt;0.001 Attack duration, median (IQR) years 3(2-4) 3(2-4) 0.325 Presence of at least one M694V mutation (%) 526(46%) 390(60%) &lt;0.001 Presence of abdominal pain in the initial attack (%) 936(81%) 669(81%) 0.926 Presence of fever in the initial attack (%) 855(74%) 592(72%) 0.281 Presence of chest pain in the initial attack (%) 218(19%) 199(24%) 0.005 Presence of arthritis in the initial attack (%) 330(29%) 215(26%) 0.224 Presence of arthralgia in the initial attack (%) 213(19%) 170(21%) 0.223 Presence of myalgia in the initial attack (%) 45(4%) 65(8%) &lt;0.001 Presence of erysipelas like erythema in the initial attack (%) 31(3%) 36(4%) 0.041 Presence of positive family history (%) 652(57%) 502(61%) 0.046 Conclusion There was some increase in the diagnostic delay in 2011-2021 compared to 2000-2010. This may be partly due to the later onset of symptoms in patients diagnosed in 2011-2021, which could have led the physicians to consider other differential diagnoses. Nevertheless, diagnostic delay in FMF still seems a prevalent problem that should be addressed to prevent excess morbidity and mortality. References [1]Erdogan M, Ugurlu S, Ozdogan H, Seyahi E. Familial Mediterranean fever: misdiagnosis and diagnostic delay in Turkey. Clin Exp Rheumatol. 2019;37 Suppl 121(6):119-124. Disclosure of Interests None declared